Prevalence of attention-deficit/hyperactivity disorder and intellectual disability among children with hydrocephalus

OBJECTIVE Little is known about the prevalence of attention-deficit/hyperactivity disorder (ADHD) in children with hydrocephalus. In this study, the authors assessed the prevalence of ADHD and its association with clinical and demographic factors, including intellectual disability (ID), a potential factor that can confound the diagnosis of ADHD. METHODS The authors conducted a cross-sectional study of children 6-12 years of age with hydrocephalus using parent telephone surveys. The Child and Adolescent Intellectual Disability Screening Questionnaire (CAIDS-Q) and the National Institute for Children's Health Quality (NICHQ) Vanderbilt Assessment Scale were used to screen for ID and ADHD, respectively. Among children without ID, the authors identified those with ADHD and calculated a prevalence estimate and 95% confidence interval (Wald method). Logistic regression analysis was conducted to compare children with ADHD with those without ADHD based on demographics, family income, parental educational, etiology of hydrocephalus, and primary treatment. As a secondary analysis, the authors compared subjects with ID with those without using the same variables. Multivariable analysis was used to identify factors with independent association with ADHD and ID. RESULTS A total of 147 primary caregivers responded to the telephone questionnaire. Seventy-two children (49%) met the cutoff score for ID (CAIDS-Q). The presence of ID was significantly associated with lower family income (p < 0.001). Hydrocephalus etiology (p = 0.051) and initial treatment (p = 0.06) approached significance. Of children without ID (n = 75), 25 demonstrated a likely diagnosis of ADHD on the NICHQ, yielding a prevalence estimate of 0.33 (95% CI 0.22-0.44). No clinical or demographic variable showed significant association with ADHD. CONCLUSIONS These data indicate that the prevalence of ADHD among children with hydrocephalus (33%) is higher than among the general population (estimated prevalence in Alabama is 12.5%). ID is also common (49%). Routine screening for ADHD and ID in children with hydrocephalus may help to ensure that adequate resources are provided to optimize functional outcomes across development.